/* $Id$ */ /** @file follow_track.hpp Template function for track followers */ #ifndef FOLLOW_TRACK_HPP #define FOLLOW_TRACK_HPP #include "yapf.hpp" /** Track follower helper template class (can serve pathfinders and vehicle * controllers). See 6 different typedefs below for 3 different transport * types w/ of w/o 90-deg turns allowed */ template <TransportType Ttr_type_, bool T90deg_turns_allowed_ = true> struct CFollowTrackT : public FollowTrack_t { CPerformanceTimer* m_pPerf; FORCEINLINE CFollowTrackT(const Vehicle* v = NULL, CPerformanceTimer* pPerf = NULL) { Init(v, pPerf); } FORCEINLINE void Init(const Vehicle* v, CPerformanceTimer* pPerf) { assert(!IsRailTT() || (v != NULL && v->type == VEH_TRAIN)); m_veh = v; m_pPerf = pPerf; // don't worry, all is inlined so compiler should remove unnecessary initializations m_new_tile = INVALID_TILE; m_new_td_bits = TRACKDIR_BIT_NONE; m_exitdir = INVALID_DIAGDIR; m_is_station = m_is_bridge = m_is_tunnel = false; m_tiles_skipped = 0; } FORCEINLINE static TransportType TT() {return Ttr_type_;} FORCEINLINE static bool IsWaterTT() {return TT() == TRANSPORT_WATER;} FORCEINLINE static bool IsRailTT() {return TT() == TRANSPORT_RAIL;} FORCEINLINE static bool IsRoadTT() {return TT() == TRANSPORT_ROAD;} FORCEINLINE static bool Allow90degTurns() {return T90deg_turns_allowed_;} /** main follower routine. Fills all members and return true on success. * Otherwise returns false if track can't be followed. */ FORCEINLINE bool Follow(TileIndex old_tile, Trackdir old_td) { m_old_tile = old_tile; m_old_td = old_td; assert((GetTileTrackStatus(m_old_tile, TT()) & TrackdirToTrackdirBits(m_old_td)) != 0); m_exitdir = TrackdirToExitdir(m_old_td); if (EnteredDepot()) return true; if (!CanExitOldTile()) return false; FollowTileExit(); if (!QueryNewTileTrackStatus()) return TryReverse(); if (!CanEnterNewTile()) return false; m_new_td_bits &= DiagdirReachesTrackdirs(m_exitdir); if (!Allow90degTurns()) m_new_td_bits &= (TrackdirBits)~(int)TrackdirCrossesTrackdirs(m_old_td); return (m_new_td_bits != TRACKDIR_BIT_NONE); } protected: /** Follow the m_exitdir from m_old_tile and fill m_new_tile and m_tiles_skipped */ FORCEINLINE void FollowTileExit() { m_is_station = m_is_bridge = m_is_tunnel = false; m_tiles_skipped = 0; // extra handling for tunnels in our direction if (IsTunnelTile(m_old_tile)) { DiagDirection tunnel_enterdir = GetTunnelDirection(m_old_tile); if (tunnel_enterdir == m_exitdir) { // we are entering the tunnel FindLengthOfTunnelResult flotr = FindLengthOfTunnel(m_old_tile, m_exitdir); m_new_tile = flotr.tile; m_is_tunnel = true; m_tiles_skipped = flotr.length - 1; return; } assert(ReverseDiagDir(tunnel_enterdir) == m_exitdir); } // extra handling for bridge ramp in our direction if (IsBridgeTile(m_old_tile)) { DiagDirection bridge_enterdir = GetBridgeRampDirection(m_old_tile); if (bridge_enterdir == m_exitdir) { // we are entering the bridge ramp m_new_tile = GetOtherBridgeEnd(m_old_tile); uint32 bridge_length = GetBridgeLength(m_old_tile, m_new_tile); m_tiles_skipped = bridge_length; m_is_bridge = true; return; } assert(ReverseDiagDir(bridge_enterdir) == m_exitdir); } // normal or station tile, do one step TileIndexDiff diff = TileOffsByDiagDir(m_exitdir); m_new_tile = TILE_ADD(m_old_tile, diff); // special handling for stations if (IsRailTT() && IsRailwayStationTile(m_new_tile)) { m_is_station = true; } else if (IsRoadTT() && IsRoadStopTile(m_new_tile)) { m_is_station = true; } else { m_is_station = false; } } /** stores track status (available trackdirs) for the new tile into m_new_td_bits */ FORCEINLINE bool QueryNewTileTrackStatus() { CPerfStart perf(*m_pPerf); if (IsRailTT() && GetTileType(m_new_tile) == MP_RAILWAY && IsPlainRailTile(m_new_tile)) { m_new_td_bits = (TrackdirBits)(GetTrackBits(m_new_tile) * 0x101); } else { uint32 ts = GetTileTrackStatus(m_new_tile, TT()); m_new_td_bits = (TrackdirBits)(ts & TRACKDIR_BIT_MASK); } return (m_new_td_bits != TRACKDIR_BIT_NONE); } /** return true if we can leave m_old_tile in m_exitdir */ FORCEINLINE bool CanExitOldTile() { // road stop can be left at one direction only unless it's a drive-through stop if (IsRoadTT() && IsStandardRoadStopTile(m_old_tile)) { DiagDirection exitdir = GetRoadStopDir(m_old_tile); if (exitdir != m_exitdir) return false; } // road depots can be also left in one direction only if (IsRoadTT() && IsTileDepotType(m_old_tile, TT())) { DiagDirection exitdir = GetRoadDepotDirection(m_old_tile); if (exitdir != m_exitdir) return false; } return true; } /** return true if we can enter m_new_tile from m_exitdir */ FORCEINLINE bool CanEnterNewTile() { if (IsRoadTT() && IsStandardRoadStopTile(m_new_tile)) { // road stop can be entered from one direction only unless it's a drive-through stop DiagDirection exitdir = GetRoadStopDir(m_new_tile); if (ReverseDiagDir(exitdir) != m_exitdir) return false; } // road and rail depots can also be entered from one direction only if (IsRoadTT() && IsTileDepotType(m_new_tile, TT())) { DiagDirection exitdir = GetRoadDepotDirection(m_new_tile); if (ReverseDiagDir(exitdir) != m_exitdir) return false; // don't try to enter other player's depots if (GetTileOwner(m_new_tile) != m_veh->owner) { return false; } } if (IsRailTT() && IsTileDepotType(m_new_tile, TT())) { DiagDirection exitdir = GetRailDepotDirection(m_new_tile); if (ReverseDiagDir(exitdir) != m_exitdir) return false; } // rail transport is possible only on tiles with the same owner as vehicle if (IsRailTT() && GetTileOwner(m_new_tile) != m_veh->owner) { // different owner return false; } // rail transport is possible only on compatible rail types if (IsRailTT()) { RailType rail_type = GetTileRailType(m_new_tile); if (!HASBIT(m_veh->u.rail.compatible_railtypes, rail_type)) { // incompatible rail type return false; } } // tunnel holes and bridge ramps can be entered only from proper direction if (!IsWaterTT() && IsTileType(m_new_tile, MP_TUNNELBRIDGE)) { if (IsTunnel(m_new_tile)) { if (!m_is_tunnel) { DiagDirection tunnel_enterdir = GetTunnelDirection(m_new_tile); if (tunnel_enterdir != m_exitdir) return false; } } else if (IsBridge(m_new_tile)) { if (!m_is_bridge) { DiagDirection ramp_enderdir = GetBridgeRampDirection(m_new_tile); if (ramp_enderdir != m_exitdir) return false; } } } // special handling for rail stations - get to the end of platform if (IsRailTT() && m_is_station) { // entered railway station // get platform length uint length = GetStationByTile(m_new_tile)->GetPlatformLength(m_new_tile, TrackdirToExitdir(m_old_td)); // how big step we must do to get to the last platform tile; m_tiles_skipped = length - 1; // move to the platform end TileIndexDiff diff = TileOffsByDiagDir(m_exitdir); diff *= m_tiles_skipped; m_new_tile = TILE_ADD(m_new_tile, diff); return true; } return true; } /** return true if we entered depot and reversed inside */ FORCEINLINE bool EnteredDepot() { // rail and road depots cause reversing if (!IsWaterTT() && IsTileDepotType(m_old_tile, TT())) { DiagDirection exitdir = IsRailTT() ? GetRailDepotDirection(m_old_tile) : GetRoadDepotDirection(m_old_tile); if (exitdir != m_exitdir) { // reverse m_new_tile = m_old_tile; m_new_td_bits = TrackdirToTrackdirBits(ReverseTrackdir(m_old_td)); m_exitdir = exitdir; m_tiles_skipped = 0; m_is_tunnel = m_is_bridge = m_is_station = false; return true; } } return false; } /** return true if we successfully reversed at end of road/track */ FORCEINLINE bool TryReverse() { if (IsRoadTT()) { // if we reached the end of road, we can reverse the RV and continue moving m_exitdir = ReverseDiagDir(m_exitdir); // new tile will be the same as old one m_new_tile = m_old_tile; // set new trackdir bits to all reachable trackdirs QueryNewTileTrackStatus(); m_new_td_bits &= DiagdirReachesTrackdirs(m_exitdir); if (m_new_td_bits != TRACKDIR_BIT_NONE) { // we have some trackdirs reachable after reversal return true; } } return false; } public: /** Helper for pathfinders - get min/max speed on the m_old_tile/m_old_td */ int GetSpeedLimit(int *pmin_speed = NULL) { int min_speed = 0; int max_speed = INT_MAX; // no limit // for now we handle only on-bridge speed limit if (!IsWaterTT() && IsBridgeTile(m_old_tile)) { int spd = _bridge[GetBridgeType(m_old_tile)].speed; if (IsRoadTT()) spd *= 2; if (max_speed > spd) max_speed = spd; } // if min speed was requested, return it if (pmin_speed) *pmin_speed = min_speed; return max_speed; } }; typedef CFollowTrackT<TRANSPORT_WATER, true > CFollowTrackWater; typedef CFollowTrackT<TRANSPORT_ROAD , true > CFollowTrackRoad; typedef CFollowTrackT<TRANSPORT_RAIL , true > CFollowTrackRail; typedef CFollowTrackT<TRANSPORT_WATER, false> CFollowTrackWaterNo90; typedef CFollowTrackT<TRANSPORT_ROAD , false> CFollowTrackRoadNo90; typedef CFollowTrackT<TRANSPORT_RAIL , false> CFollowTrackRailNo90; #endif /* FOLLOW_TRACK_HPP */